U.S. patent number 9,530,376 [Application Number 14/600,133] was granted by the patent office on 2016-12-27 for driving device and driving method of liquid crystal display device and liquid crystal display device.
This patent grant is currently assigned to BEIJING BOE DISPLAY TECHNOLOGY CO., LTD., BOE TECHNOLOGY GROUP CO., LTD.. The grantee listed for this patent is BEIJING BOE DISPLAY TECHNOLOGY CO., LTD., BOE TECHNOLOGY GROUP CO., LTD.. Invention is credited to Shuai Hou, Yiqiang Lai, Bin Zhang, Chunbing Zhang, Liang Zhang.
United States Patent |
9,530,376 |
Zhang , et al. |
December 27, 2016 |
Driving device and driving method of liquid crystal display device
and liquid crystal display device
Abstract
The present disclosure relates to a driving device and a driving
method of a liquid crystal display device and a liquid crystal
display device. The liquid crystal display device comprises a
display panel. The driving method comprising following steps of:
displaying a current image by driving the display panel in a
current reverse driving mode; detecting a variation value of a
common voltage of the display panel during a prescribed period of
time, and determining whether the variation value of the common
voltage is greater than a prescribed threshold voltage variation;
and in case that the variation value of the common voltage is
greater than the prescribed threshold voltage variation,
determining an occurrence of an image flickering and changing the
current reverse driving mode. According to the present disclosure,
the flickering of the liquid crystal display device can be
reduced.
Inventors: |
Zhang; Chunbing (Beijing,
CN), Zhang; Bin (Beijing, CN), Hou;
Shuai (Beijing, CN), Lai; Yiqiang (Beijing,
CN), Zhang; Liang (Beijing, CN) |
Applicant: |
Name |
City |
State |
Country |
Type |
BOE TECHNOLOGY GROUP CO., LTD.
BEIJING BOE DISPLAY TECHNOLOGY CO., LTD. |
Beijing
Beijing |
N/A
N/A |
CN
CN |
|
|
Assignee: |
BOE TECHNOLOGY GROUP CO., LTD.
(Beijing, CN)
BEIJING BOE DISPLAY TECHNOLOGY CO., LTD. (Beijing,
CN)
|
Family
ID: |
52792797 |
Appl.
No.: |
14/600,133 |
Filed: |
January 20, 2015 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20160203784 A1 |
Jul 14, 2016 |
|
Foreign Application Priority Data
|
|
|
|
|
Jan 12, 2015 [CN] |
|
|
2015 1 0015180 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G09G
3/3696 (20130101); G09G 3/3611 (20130101); G09G
3/3614 (20130101); G09G 2320/0247 (20130101) |
Current International
Class: |
G09G
3/36 (20060101) |
Field of
Search: |
;345/211,204,87-104 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
101995694 |
|
Mar 2011 |
|
CN |
|
102262867 |
|
Nov 2011 |
|
CN |
|
Other References
First Chinese Office Action dated Jul. 5, 2016; Appln. No.
201510015180.5. cited by applicant.
|
Primary Examiner: Sherman; Stephen
Attorney, Agent or Firm: Ladas & Parry LLP
Claims
What is claimed is:
1. A driving method of a liquid crystal display device, the liquid
crystal display device comprising a display panel, the method
comprising following steps of: S610, displaying a current image by
driving the display panel in a current reverse driving mode; S620,
detecting a variation value of a common voltage of the display
panel during a prescribed period of time, and determining whether
the variation value of the common voltage is greater than a
prescribed threshold voltage variation; and S630, changing the
current reverse driving mode in case that the variation value of
the common voltage is greater than the prescribed threshold voltage
variation and determining an occurrence of an image flickering,
wherein the step S620 further comprises following steps of:
comparing a common voltage value and a prescribed reference voltage
value at a start point of the prescribed period of time, and
generating a first logic value based on the comparison; comparing a
common voltage value and a prescribed reference voltage value at an
end point of the prescribed period of time, and generating a second
logic value based on the comparison; comparing the first logic
value and the second logic value, in case that the first logic
value is not equal to the second logic value, determining that the
variation value of the common voltage is greater than the
prescribed threshold voltage variation; in case that the first
logic value is equal to the second logic value, determining that
the variation value of the common voltage is not greater than the
prescribed threshold voltage variation.
2. The driving method according to claim 1, wherein in case of
determining the occurrence of the image flickering, the driving
method further comprises storing the current image as a flickering
pattern in a flickering pattern storage device of the liquid
crystal display device.
3. The driving method according to claim 2, wherein the flickering
pattern comprises color and polarity of each pixel in the current
image displayed.
4. The driving method according to claim 3, after the step of S630,
further comprising searching for the current image in the
flickering pattern storage device, determining whether the changed
current image is one of flickering patterns stored in the
flickering pattern storage device; and changing the current reverse
driving mode in case that the changed current image is the
flickering pattern stored in one of the flickering patterns storage
device.
5. The driving method according to claim 1, wherein the current
reverse driving mode comprises a point reverse driving mode, a row
reverse driving mode or a column reverse driving mode.
6. A liquid crystal display device, comprising: a display panel
configured for displaying a current image in a current reverse
driving mode; the display panel comprising: a common voltage
detecting device configured for detecting a variation value of a
common voltage of the display panel during a prescribed period of
time, and determining whether the variation value of the common
voltage is greater than a prescribed threshold voltage variation;
and a driving mode control device configured for receiving the
determination result from the common voltage detecting device, and
in case that the variation value of the common voltage is greater
than the prescribed threshold voltage variation, determining an
occurrence of an image flickering and changing the current reverse
driving mode, wherein the common voltage detecting device
comprises: a voltage comparing device comprising a first input
terminal, a second terminal, and an output terminal and configured
for comparing a common voltage value and a prescribed reference
voltage value at a start point of the prescribed period of time and
generating a first logic value based on the comparison; comparing a
common voltage value and a prescribed reference voltage value at an
end point of the prescribed period of time and generating a second
logic value based on the comparison; the driving mode control
device configured such that in case that the first logic value is
not equal to the second logic value, determining that the variation
value of the common voltage is greater than the prescribed
threshold voltage variation; and in case that the first logic value
is equal to the second logic value, and determining that the
variation value of the common voltage is not greater than the
prescribed threshold voltage variation.
7. The liquid crystal display device according to claim 6, wherein
the display panel further comprises a flickering pattern storage
device configured for storing the current image as a flickering
pattern in case of determining the occurrence of the image
flickering.
8. The liquid crystal display device according to claim 7, wherein
the flickering pattern comprises color and polarity of each pixel
in the current image displayed.
9. The liquid crystal display device according to claim 8, wherein
the driving mode control device is further configured for, after
changing the current reverse driving mode, searching for the
changed current image in the flickering pattern storage device and
changing the current reverse driving mode in case that the changed
current image is the flickering pattern stored in one of flickering
patterns storage device.
10. The liquid crystal display device according to claim 6, wherein
the current reverse driving mode comprises a point reverse driving
mode, a row reverse driving mode or a column reverse driving
mode.
11. The liquid crystal display device according to claim 6, wherein
the voltage comparing device is disposed in a TCON controller of
the display panel.
12. The liquid crystal display device according to claim 11,
wherein the voltage comparing device further comprises a common
voltage sampling circuit configured for relaying the common voltage
of the display panel to a first input terminal of the voltage
comparing device.
13. A driving device of a display panel, the display panel
configured for displaying a current image in a current reverse
driving mode, the driving device comprising: a common voltage
detecting device configured for detecting a variation value of a
common voltage of the display panel during a prescribed period of
time, and determining whether the variation value of the common
voltage is greater than a prescribed threshold voltage variation;
and a driving mode control device configured for receiving the
determination result from the common voltage detecting device, and
in case that the variation value of the common voltage is greater
than the prescribed threshold voltage variation, determining an
occurrence of an image flickering and changing the current reverse
driving mode, wherein the common voltage detecting device
comprises: a voltage comparing device comprising a first input
terminal, a second terminal, and an output terminal and configured
for comparing a common voltage value and a prescribed reference
voltage value at a start point of the prescribed period of time and
generating a first logic value based on the comparison; comparing a
common voltage value and a prescribed reference voltage value at an
end point of the prescribed period of time and generating a second
logic value based on the comparison; the driving mode control
device configured such that in case that the first logic value is
not equal to the second logic value, determining that the variation
value of the common voltage is greater than the prescribed
threshold voltage variation; and in case that the first logic value
is equal to the second logic value, and determining that the
variation value of the common voltage is not greater than the
prescribed threshold voltage variation.
14. The driving device according to claim 13, further comprising a
flickering pattern storage device configured for storing the
current image as a flickering pattern in case of determining the
occurrence of the image flickering, the flickering pattern
comprises color and polarity of each pixel in the current image
displayed.
15. The driving device according to claim 14, wherein the driving
mode control device is further configured for, after changing the
current reverse driving mode, searching for the changed current
image in the flickering pattern storage device and changing the
current reverse driving mode in case that the changed current image
displayed in the current reverse driving mode is one of flickering
patterns stored in the flickering pattern storage device.
16. The driving device according to claim 15, wherein the current
reverse driving mode comprises a point reverse driving mode, a row
reverse driving mode or a column reverse driving mode.
17. The driving device according to claim 13, wherein the voltage
comparing device is disposed in a TCON controller of the display
panel, and the voltage comparing device further comprises a common
voltage sampling circuit configured for relaying the common voltage
of the display panel to a first input terminal of the voltage
comparing device.
Description
FIELD
The present disclosure relates to a driving device and a driving
method of a liquid crystal display device and a liquid crystal
display device.
BACKGROUND
As a current mainstream display device, the liquid crystal display
dominates the current flat display market due to compact slim
design with low power consumption. One of the major issues of the
current liquid crystal display device is the flickering of the
displayed image, which adversely affected the display quality of
the display device.
SUMMARY
The present disclosure provides a driving method of a liquid
crystal display device. The liquid crystal display device comprises
a display panel. The method comprises following steps of: S610,
displaying a current image by driving the display panel in a
current reverse driving mode; S620, detecting a variation value of
a common voltage of the display panel during a prescribed period of
time, and determining whether the variation value of the common
voltage is greater than a prescribed threshold voltage variation;
and S630, changing the current reverse driving mode in case that
the variation value of the common voltage is greater than the
prescribed threshold voltage variation and determining an
occurrence of an image flickering.
In one example, in case of determining the occurrence of the image
flickering, the driving method further comprises storing the
current image as a flickering pattern in a flickering pattern
storage device of the liquid crystal display device. The flickering
pattern comprises color and polarity of each pixel in the current
image displayed. After the step of S630, the method further
comprises searching for the current image in the flickering pattern
storage device, determining whether the current image is a
flickering pattern stored in the flickering pattern storage device;
and changing the current reverse driving mode in case that the
current image is the flickering pattern stored in the flickering
pattern storage device.
In one example, the current reverse driving mode comprises a point
reverse driving mode, a row reverse driving mode or a column
reverse driving mode.
In one example, the step S620 further comprises following steps of:
comparing a common voltage value and a prescribed reference voltage
value at a start point of the prescribed period of time, and
generating a first logic value based on the comparison; comparing a
common voltage value and a prescribed reference voltage value at an
end point of the prescribed period of time, and generating a second
logic value based on the comparison; comparing the first logic
value and the second logic value, in case that the first logic
value is not equal to the second logic value, determining that the
variation value of the common voltage is greater than the
prescribed threshold voltage variation; in case that the first
logic value is equal to the second logic value, determining that
the variation value of the common voltage is not greater than the
prescribed threshold voltage variation.
The present disclosure further provides a liquid crystal display
device, comprising a display panel configured for displaying a
current image in a current reverse driving mode. The display panel
comprises: a common voltage detecting device configured for
detecting a variation value of a common voltage of the display
panel during a prescribed period of time, and determining whether
the variation value of the common voltage is greater than a
prescribed threshold voltage variation; and a driving mode control
device configured for receiving the determination result from the
common voltage detecting device, and in case that the variation
value of the common voltage is greater than the prescribed
threshold voltage variation, determining an occurrence of an image
flickering and changing the current reverse driving mode.
In one example, the display panel further comprises a flickering
pattern storage device configured for storing the current image as
a flickering pattern in case of determining the occurrence of the
image flickering. The driving mode control device is further
configured for searching for the current image in the flickering
pattern storage device and changing the current reverse driving
mode in case that the current image is the flickering pattern
stored in the flickering pattern storage device.
In one example, the common voltage detecting device comprises a
voltage comparing device comprising a first input terminal, a
second terminal, and an output terminal and configured for
comparing a common voltage value and a prescribed reference voltage
value at a start point of the prescribed period of time and
generating a first logic value based on the comparison; comparing a
common voltage value and a prescribed reference voltage value at an
end point of the prescribed period of time and generating a second
logic value based on the comparison. The driving mode control
device is configured so that in case that the first logic value is
not equal to the second logic value, determining that the variation
value of the common voltage is greater than the prescribed
threshold voltage variation; and in case that the first logic value
is equal to the second logic value, and determining that the
variation value of the common voltage is not greater than the
prescribed threshold voltage variation.
In one example, the voltage comparing device is disposed in a TCON
controller of the display panel.
In one example, the voltage comparing device further comprises a
common voltage sampling circuit configured for relaying the common
voltage of the display panel to a first input terminal of the
voltage comparing device.
The present disclosure further provides a driving device of a
display panel. The display panel is configured for displaying a
current image in a current reverse driving mode. The driving device
comprises: a common voltage detecting device configured for
detecting a variation value of a common voltage of the display
panel during a prescribed period of time, and determining whether
the variation value of the common voltage is greater than a
prescribed threshold voltage variation; and a driving mode control
device configured for receiving the determination result from the
common voltage detecting device, and in case that the variation
value of the common voltage is greater than the prescribed
threshold voltage variation, determining an occurrence of an image
flickering and changing the current reverse driving mode.
In one example, the driving device further comprises a flickering
pattern storage device configured for storing the current image as
a flickering pattern in case of determining the occurrence of the
image flickering, the flickering pattern comprises color and
polarity of each pixel in the current image displayed.
According to the present disclosure, the degree of variation of the
common voltage is used as a measure of the image flickering, and a
different reverse driving mode is used if the image flickering
occurs, thus avoiding that the pixels displaying color especially
the same color in the current image have the same polarity, thereby
reducing or eliminating the image flickering.
BRIEF DESCRIPTION OF THE DRAWINGS
In order to clearly illustrate the technical solution of the
present disclosure, the technical solution of the present
disclosure will be further described with reference to the
following drawings. The drawings described in the following are
only related to a part of embodiments of the technical solution of
the present disclosure.
FIGS. 1-4 are schematic views showing reverse driving modes of a
liquid crystal display device;
FIG. 5 is a schematic view of a display panel of a liquid crystal
display device displaying a pattern with a flickering
phenomenon;
FIG. 6 is a flowchart of a driving method of a liquid crystal
display device according to a first embodiment of the present
disclosure;
FIG. 7 is a flowchart of a driving method of a liquid crystal
display device according to a second embodiment of the present
disclosure;
FIG. 8 is a schematic view showing changing a pattern with
flickering phenomenon as shown in FIG. 5 as a pattern without
flickering according to the driving method of the present
disclosure;
FIG. 9 is a schematic view of a liquid crystal display device
according to an embodiment of the present disclosure; and
FIG. 10 is a schematic view of a voltage comparing device of a
liquid crystal display device according to an embodiment of the
present disclosure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The technical solution of the embodiments of the present disclosure
will be described clearly and fully in connection with the drawings
of the embodiments of the present disclosure. It is obvious that
the described embodiments are just a part but not all of the
embodiments of the present disclosure. Based on the described
embodiments of the present disclosure, those skilled in the art can
obtain all other embodiment without any inventive work, which all
fall into the scope of the claimed invention.
Unless otherwise defined, technical terms or scientific terms used
herein shall have a common meaning known by those skilled in the
art of the present disclosure. Words and expressions such as
"first", "second" and the like used in the description and claims
of the patent application of the present disclosure do not denote
any sequence, quantity or importance, but distinguish different
components. Likewise, words such as "a", "an" and the like do not
denote quantitative restrictions, but denote the presence of at
least one. Words such as "connected", "connecting" and the like are
not restricted to physical or mechanical connections, but may
include electrical connections, regardless of direct or indirect
connections. Words such as "up", "below", "left", "right", etc.,
are only used to denote the relative positional relationship. Upon
the absolute position of the described object changes, the relative
positional relationship change correspondingly.
In a driving method of the liquid crystal display device, it is
necessary to apply an electrical field with a changed polarity so
as to reduce the fatigue of the liquid crystal, thereby achieving a
good display quality. This is referred as a reverse driving mode of
a liquid crystal display device. The reverse driving mode includes
a frame reverse driving mode, a point reverse driving mode, a row
reverse driving mode or a column reverse driving mode. FIGS. 1-4
are schematic views showing the frame reverse driving mode, the
point reverse driving mode, the row reverse driving mode or the
column reverse driving mode of a liquid crystal display device,
respectively. Each pixel is represented by a block and the signs
"+" and "-" in the blocks refer to two opposing polarities of the
liquid crystals in the respective pixels. As shown in FIG. 1, in
the frame reverse driving mode, all pixels in a frame of image have
the same polarity. As shown in FIG. 2, in the point reverse driving
mode, each pixel has a different polarity than the polarity of an
adjacent pixel. As shown in FIG. 3, in the row reverse driving
mode, pixels in a row in a frame of image have the same polarity,
but have a different polarity than the polarity in the pixels in
the adjacent row. As shown in FIG. 4, in the column reverse driving
mode, pixels in a column in a frame of image have the same
polarity, but have a different polarity than the polarity in the
pixels in the adjacent column. In the display of the next frame of
image, the polarities of all pixels will be reversed.
When the pixels of the pattern displayed in a frame of image have
the same polarity, the liquid crystal display device has the most
severe flickering, compared with the same pattern displayed with
different polarities. For example, as shown in FIG. 5, the pixels
of the pattern displayed in a frame of image marked with a grey
color have the same negative polarity. In this case, the pattern
displayed on the liquid crystal display device will have the most
severe flickering. In addition, since the human eyes are more
susceptible to the brightness variation of a green pixel, in case
of the pixels of the displayed pattern have a green color, the
flickering observed by the human eyes will be more severe. That is,
in case of majority of pixels in the displayed pattern have a same
color for example a green color and a same polarity, the flickering
of the displayed pattern in the liquid crystal display device
sensed by the human eyes will be more severe. Therefore, the
present inventor proposes changing the polarities of the pixels by
changing the reverse driving mode of the display panel of the
liquid crystal display device, thus avoiding majority of the pixels
displaying the pattern have the same polarity. In this case, the
flickering of the liquid crystal display device is reduced or
eliminated.
The present inventors further discover that the image with severe
flickering introduces a significant variation in the common
voltage. Therefore, it can be determined whether there is
flickering in the current image displayed in the liquid crystal
display device by detecting the variation of the common
voltage.
To this end, the present disclosure provides a driving method of a
liquid crystal display device. The liquid crystal display device
includes a display panel. FIG. 6 is a flowchart of a driving method
of a liquid crystal display device according to a first embodiment
of the present disclosure. As shown in FIG. 6, the driving method
includes following steps: S610, displaying a current image by
driving the display panel in a current reverse driving mode; S620,
detecting a variation value of a common voltage of the display
panel during a prescribed period of time, and determining whether
the variation value of the common voltage is greater than a
prescribed threshold voltage variation; and S630, changing the
current reverse driving mode in case that the variation value of
the common voltage is greater than the prescribed threshold voltage
variation and determining an occurrence of an image flickering and
returning to step S610, that is displaying a current image by
driving the display panel in a changed current reverse driving
mode; or returning to step S610 directly of displaying the current
image by driving the display panel in the current reverse driving
mode continuously in case that the variation value of the common
voltage is not greater than the prescribed threshold voltage
variation and determining no occurrence of an image flickering.
In the above method, in case that majority of pixels displaying the
pattern in the current frame of image have the same polarity so
that the image has a flickering phenomenon, a different reverse
driving mode can be used for displaying the pattern in the next
frame of the image so as to change the polarity distribution of the
pattern, thereby reducing or avoiding the occurrence of the
flickering. For example, as shown in FIG. 5, the pixels represented
by grey color for displaying a pattern in a frame of image have the
same negative polarity in the point reverse driving mode, therefore
the flickering occurs in such pattern. According to the method of
the present disclosure, a different reverse driving mode for
example a row reverse driving mode is used in the step S630, as
shown in FIG. 8, so that the pixels for displaying the pattern in
the next frame of image have both positive and negative polarity
and substantial uniform distribution, thereby reducing or avoiding
the occurrence of the flickering.
In the embodiments of the present disclosure, the reverse driving
mode includes a point reverse driving mode, a row reverse driving
mode or a column reverse driving mode.
In one example, the step S620 can include: comparing a common
voltage value and a prescribed reference voltage value at a start
point of the prescribed period of time, and generating a first
logic value based on the comparison; comparing a common voltage
value and a prescribed reference voltage value at an end point of
the prescribed period of time, and generating a second logic value
based on the comparison; comparing the first logic value and the
second logic value, in case that the first logic value is not equal
to the second logic value, determining that the variation value of
the common voltage is greater than the prescribed threshold voltage
variation; in case that the first logic value is equal to the
second logic value, determining that the variation value of the
common voltage is not greater than the prescribed threshold voltage
variation.
In particular, the prescribed reference voltage can be a lower
threshold of the common voltage. In case that the common voltage
detected at the start point of the prescribed period of time is
greater than the lower threshold, the first logic value can be set
as "1". In case that the common voltage detected at the end point
of the prescribed period of time is still greater than the lower
threshold, the second logic value can also be set as "1". In this
case, the first logic value is equal to the second logic value,
thereby determining that the variation of common voltage does not
introduce a flickering. On the contrary, in case that the common
voltage detected at the start point of the prescribed period of
time is greater that the lower threshold, the first logic value can
be set as "1", whereas the common voltage detected at the end point
of the prescribed period of time is less than the lower threshold,
the second logic value can also be set as "0". In this case, the
first logic value is not equal to the second logic value, thereby
determining that the variation of common voltage exceeds the
prescribed threshold voltage variation and introduces a flickering.
In another example, the prescribed reference voltage can be an
upper threshold of the common voltage. In case that the common
voltage detected at the start point of the prescribed period of
time is less than the upper threshold, the first logic value can be
set as "1". In case that the common voltage detected at the end
point of the prescribed period of time is still less than the upper
threshold, the second logic value can also be set as "1". In this
case, the first logic value is equal to the second logic value,
thereby determining that the variation of common voltage does not
introduce a flickering. On the contrary, in case that the common
voltage detected at the start point of the prescribed period of
time is less than the upper threshold, the first logic value can be
set as "1", whereas the common voltage detected at the end point of
the prescribed period of time is greater than the upper threshold,
the second logic value can also be set as "0". In this case, the
first logic value is not equal to the second logic value, thereby
determining that the variation of common voltage exceeds the
prescribed threshold voltage variation and introduces a
flickering.
In addition, the prescribed period of time can be set for example
shorter than the period of time for displaying one frame of image
in the display panel of the liquid crystal display device, thereby
the occurrence of flickering can determined during the display of
that frame of image.
FIG. 7 is a flowchart of a driving method of a liquid crystal
display device according to a second embodiment of the present
disclosure. The driving method of a liquid crystal display device
according to a second embodiment of the present disclosure includes
the steps of S710, S720 and S730, which are substantially the same
as the steps of S610, S620 and S630 in the first embodiment and
will not be described repeatedly. Furthermore, the driving method
according to a second embodiment of the present disclosure further
comprises a step of S725, storing the current image as a flickering
pattern in a flickering pattern storage device of the liquid
crystal display device in case of determining occurrence of the
flickering. The flickering pattern includes color and polarity of
each pixel in the current image displayed. The skilled in the art
can understand that steps of S725 and S730 can be performed
sequentially or simultaneously, or step S730 can be performed
before step S725. Correspondingly, after the step of S730, that is,
after changing the current reverse driving mode, the driving method
can further include a step of searching for the current image
driven by the changed reverse driving mode in the flickering
pattern storage device. In case that the current image is the
flickering pattern stored in the flickering pattern storage device,
then the current reverse driving mode is changed directly without
detecting the variation of the common voltage during a prescribed
period of time, thereby avoiding the flickering phenomenon.
The embodiment of the present disclosure further provides a liquid
crystal display device. FIG. 9 is a schematic view of a liquid
crystal display device according to an embodiment of the present
disclosure. As shown in FIG. 9, the liquid crystal display device
comprises: a display panel 900 configured for displaying a current
image in an effective image display region 910 with a current
reverse driving mode. The display panel 900 comprises: a common
voltage detecting device 920 configured for detecting a variation
value of a common voltage of the display panel during a prescribed
period of time, and determining whether the variation value of the
common voltage is greater than a prescribed threshold voltage
variation; and a driving mode control device 930 configured for
receiving the determination result from the common voltage
detecting device, and in case that the variation value of the
common voltage is greater than the prescribed threshold voltage
variation, determining an occurrence of an image flickering and
changing the current reverse driving mode. The driving mode control
device 930 can be implemented in circuits or ICs.
In one example, the display panel can further include a flickering
pattern storage device 940 configured for storing the current image
as a flickering pattern in case of determining the occurrence of
the image flickering. The flickering pattern storage device 940 can
be any storage device such as flash memory, and the flickering
pattern can be stored in a database in the storage device. In such
case, the driving mode control device 930 is further configured for
searching for the current image in the flickering pattern storage
device 940 and changing the current reverse driving mode in case
that the current image is the flickering pattern stored in the
flickering pattern storage device. The flickering pattern includes
color and polarity of each pixel in the current image
displayed.
In one example, the common voltage detecting device 920 includes a
voltage comparing device 922 and an optional common voltage
sampling circuit 928. FIG. 10 is a schematic view of an example of
voltage comparing device 922. The voltage comparing device 922
includes a first input terminal 923, a second terminal 924, and an
output terminal 925. The voltage comparing device 922 is configured
for comparing a common voltage value at the first input terminal
923 and a prescribed reference voltage value at the second input
terminal 924 at a start point of the prescribed period of time and
generating a first logic value at the output terminal 925 based on
the comparison; comparing a common voltage value at the first input
terminal 923 and a prescribed reference voltage value at the second
input terminal 924 at an end point of the prescribed period of time
and generating a second logic value based on the comparison at the
output terminal 925. The first logic value and the second logic
value can be a high level representing "1" and a low level
representing "0".
For example, the prescribed reference voltage can be a lower
threshold of the common voltage. In case that the common voltage
detected at the first input terminal 923 at the start point of the
prescribed period of time is greater than the lower threshold at
the second input terminal 924, the first logic value can be set as
"1". In case that the common voltage detected at the first input
terminal 923 at the end point of the prescribed period of time is
still greater than the lower threshold at the second input terminal
924, the second logic value can also be set as "1". On the
contrary, in case that the common voltage detected at the first
input terminal 923 at the start point of the prescribed period of
time is greater that the lower threshold at the second input
terminal 924, the first logic value can be set as "1", whereas the
common voltage detected at the first input terminal 923 at the end
point of the prescribed period of time is less than the lower
threshold at the second input terminal 924, the second logic value
can also be set as "0".
In this case, if the first logic value is equal to the second logic
value, the common voltage detecting device 930 determines that the
variation of common voltage does not introduce the flickering. On
the contrary, if the first logic value is not equal to the second
logic value, the common voltage detecting device 930 determines
that the variation of common voltage exceeds the prescribed
threshold voltage variation and introduces a flickering.
As shown in FIG. 9, the common voltage sampling circuit 928 relays
the common voltage of the display panel to a first input terminal
923 of the voltage comparing device 922.
As shown in FIG. 9, the voltage comparing device 924 is disposed in
a TCON controller 950 of the display panel. In addition, the
driving mode control device 930 and flickering pattern storage
device 940 can also be disposed in the TCON 950 of the display
panel 900.
The present disclosure further provides a driving device of a
display panel. The display panel is configured for displaying a
current image in a current reverse driving mode. The driving device
comprises: a common voltage detecting device 920 configured for
detecting a variation value of a common voltage of the display
panel during a prescribed period of time, and determining whether
the variation value of the common voltage is greater than a
prescribed threshold voltage variation; and a driving mode control
device 930 configured for receiving the determination result from
the common voltage detecting device, and in case that the variation
value of the common voltage is greater than the prescribed
threshold voltage variation, determining an occurrence of an image
flickering and changing the current reverse driving mode.
According to the present disclosure, the degree of variation of the
common voltage is used as a measure of the image flickering, and a
different reverse driving mode is used if the image flickering
occurs, thus avoiding that the pixels displaying color especially
the same color in the current image have the same polarity, thereby
reducing or eliminating the image flickering.
The foregoing detailed description of the invention has been
presented for purposes of illustration and description. It is not
intended to be exhaustive or to limit the invention to the precise
form disclosed. Many modifications and variations are possible in
light of the above teaching. The described embodiments were chosen
in order to best explain the principles of the invention and its
practical application to thereby enable the skilled in the art to
best utilize the invention in various embodiments and with various
modifications as are suited to the particular use contemplated. It
is intended that the scope of the invention be defined by the
claims appended hereto.
* * * * *